Field of the Invention
The invention concerns a system for assisting an operator of a technical appliance, with an image display device, of which the image is provided within the normal viewing field of the operator, for indication of operationally relevant information in the form of images or symbols.
Modern warning systems are being designed to warn the automobile operators of dangerous situations, of which the recognition has hitherto been the sole responsibility of the driver. For example, a “curve warner” provides the operator with early warning of the encountering of curves, which are too tight for the actual driving speed. Presently, this warning occurs using acoustic enunciators, for example “sharp left curve ahead,” and/or by offering optical warning signals in the dashboard or reflected into the windshield.
This type of warning system is, as a rule, so designed, that the warning of a danger only occurs when it is to be presumed that the driver has not himself recognized this danger, since otherwise the acceptance and the effect of the warning information would be ignored or lost. In many warning systems, it is however difficult or even impossible to determine or fix a suitable time point for generating the warning. On the one hand, the warning must occur early enough so that the driver can be appraised of the dangerous situation, should he not have recognized it himself. On the other hand, the warning should not occur so early, that a driver, who has already recognized the danger and intends to take appropriate measures, is unnecessarily disturbed or distracted. These two requirements can frequently not be accommodated at the same time.
The same dilemma occurs in warning or information systems for other technical apparatus other than automotive vehicles. For example, the operator of a machine or industrial apparatus is normally optically or acoustically warned or informed when particular situations occur which might possibly necessitate a rapid intervention. Too early or, as the case may be, too many warning signals could lead thereto that the attentiveness of the operator is reduced with time and important information is disregarded. On the other hand, the warning should not occur so late, that the operator might possibly not be able to react.
The invention is accomplished with providing the optical information for such a short period of time, that it is not consciously recognized, however is registered by the person. This phenomenon, referred to as “visual priming,” is described for example by A. J. Marcel in Conscious and unconscious perception: Experiments on visual masking and word recognition, Cognitive Psychology 15 (1983), Pages 197-237. The best known example of this phenomenon is the exchange of individual frames of a film sequence with frames having a completely different content, which the observer does not consciously comprehend during watching of the film, but which however do affect his perceptions or, as the case may be, his behavior.
This effect is used in the invention for sub-threshold warning, informing, or influencing of the operator of a machine. This makes possible for example a warning without distracting signals such as the illumination of lights or warning noises with conventional warning systems.
During experiments for carrying out the invention, it has been demonstrated that the sub-threshold offering of operationally relevant information in an image display, of which the image is in the normal visual field of the operator, effectively sensitizes the operator to the offered information. Thereby, the reaction time of the operator is substantially reduced when the situation, to which he was unconsciously prepared, actually occurs. The operator is however not disturbed or distracted by the information offered on the sub-threshold level. Thus, the operationally relevant information can immediately be displayed for a short period of time after the appropriate situation has been recognized, that is, without consideration as to whether the operator has initiated any manipulations.
According to the invention, an image or symbol, which reflects the operationally relevant information, is displayed at once for a short period of time, wherein the duration of the display is preferably below that of conscious recognition and above that of subconscious recognition of the operator. Therein, the threshold of subconscious recognition is defined as the display duration with which the information is just barely accepted unconsciously, that is, has an effect on the later behavior of the operator, and the conscious recognition threshold is the duration of display at which the operator becomes conscious of the information.
These two recognition thresholds can, by the way, be influenced by the size and magnitude or intensity of the displayed image and, besides this, by whether the image or symbol is offered in the center of the field of vision or at the edge. It has been shown that a short time presentation in the periphery of the visual field influences the cognition or recognition or, as the case may be, the behavior of the operator.
Basis on the condition that the operationally relevant information could be offered even in the periphery of the field of vision of the operator, the invention is suitable also for technical appliances, such as for example, an automobile.
When adapting the invention to an automobile, one employs normally one or more devices for automatic recognition of situations, which may possibly require a reaction of the automobile driver, and a device for controlling the image display device, in order to display the appropriate operationally relevant information as soon as the appropriate situation is recognized.
For recognition of dangerous situations, there can be employed for example devices for recognition of an inappropriate speed of the vehicle prior to a curve, for recognition of traffic signs, for recognition of road conditions, for recognition of traffic signals, for recognition of approach situations, for recognition of crossing situations, for recognition of pedestrians and/or for recognition of low stimulation or signal intensity and tedious driving situations.
The invention is suitable not only for sensitization with respect to dangerous situations, but rather also to sensitize automobile drivers or operators of other technical apparatus to various other important conditions without imposing or disturbing, i.e. conditions which might possibly require a reaction. Devices for recognition of various possible important situations during the operation of a vehicle, which can advantageously be combined or utilized with the present invention, are for example a navigation device and/or a device for monitoring of operational values of the vehicle, for example the status of the fuel.
The recognition signals of the above-mentioned devices can in many ways be combined with each other, in order to prepare the information and in present it in an optimal manner to the driver. For example one symbol may be a symbol, which alerts the driver below the threshold of recognition to the possible need of a fuel stop, and can be given exactly then when the navigation system determines that a filling station is being approached. The briefly displayed images or symbols can be pictures of corresponding situations, pictograms, traffic symbols, arrows or written words.
In a preferred embodiment, the image display device is a so-called heads-up display. In an automobile, one realizes a heads-up display thereby that the image information is reflected into the visual field of the driver via the windshield. The reflected image information can in a first stage or level be the conventional operating parameters such as RPM, speed, blinker, etc. and the operationally relevant information according to the invention can supplementally be reflected or reflected during an appropriate short time fade-out of the main image.
The invention is also suitable for retrofitting to vehicles, which have for example conventional individual instruments on the instrument panel. In such a case, it can be useful when all the short time images are reflected via the windshield into the visual field of the driver.
For adapting a motorcycle or other machine or vehicle, which has no suitable reflecting device such as a windshield, a heads-up display can be designed in the manner of, for example, glasses or goggles wearable by the operator.
In place of a heads-up display, the image display device can be a pixel based controllable display screen for direct viewing by the operator, for example an LCD-display on the instrument panel, upon which important operational parameters of the vehicle are represented. As already described, the briefly offered images, even when peripherally displayed, leave behind a measurable impression with the driver, so that it is not detrimental when he normally does not look directly at the image screen or, as the case may be, in complex driving situations frequently changes his direction of viewing.
For safety, the short time images can also be offered multiple times sequentially at spaced-apart time intervals. This is possible, since in accordance with the invention it is not necessary to wait to see whether the driver reacts by himself. Rather, all necessary warning or other information can be given immediately, so that substantially more time latitude exists than with conventional warning systems.
It is useful when the duration, with which the respective image or symbol is displayed for a short period of time, can be adjusted or controlled by the operator. Thereby, the operator can adapt the system precisely to his personal threshold of recognition. In order to facilitate this, the system can offer an appropriate adjustment procedure, through which the operator is guided.